@aws_auth(cognito_groups: ["users"]) works, @aws_cognito_user_pools(cognito_groups: ["users"]) doesn't

I am getting a successful response when using `@aws_auth(cognito_groups: ["users"])`. However, when I attempt to use `@aws_cognito_user_pools(cognito_groups: ["users"])`, I receive the following error:
```json
{
"errors": [
{
"path": [
"getCheck"
],
"data": null,
"errorType": "Unauthorized",
"errorInfo": null,
"locations": [
{
"line": 3,
"column": 5,
"sourceName": null
}
],
"message": "Not Authorized to access getCheck on type Query"
}
]
}
```

I am using `AMAZON_COGNITO_USER_POOLS` as the primary AppSync auth mode, with no additional auth modes. My understanding (according to docs [here](https://docs.aws.amazon.com/appsync/latest/devguide/security-authz.html#using-additional-authorization-modes)) is that these should be interchangeable if `AMAZON_COGNITO_USER_POOLS` is the only auth mode that's used.

> You can use the @aws_cognito_user_pools directive in place of the @aws_auth directive, using the same arguments.

I am able to proceed with the `@aws_auth` directive, but wanted to raise this issue as it was quite confusing to encounter.

Start with the AppSync GraphQL schema directives and the API authentication-mode configuration described in the issue, then compare @aws_auth with @aws_cognito_user_pools when AMAZON_COGNITO_USER_POOLS is the only mode enabled. Verify the behavior against the linked authorization documentation; done means the two directives have the documented equivalent authorization behavior or the discrepancy is clearly documented.

Written by the indexing model from the issue text.